Lifetime for human copyright, 20 years for corporate copyright. That’s the golden zone.
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Assuming you agree with the idea of inheritance, which is another topic, then it is unfair to deny inheritance of intellectual property. For example if your father has built a house, it will be yours when he dies, it won't become a public house. So why would a book your father wrote just before he died become public domain the moment he dies. It is unfair to those doing who are doing intellectual work, especially older people.
If you want short copyright, is would make more sense to make it 20 years, human or corporate, like patents.